Thrombosis of the internal carotid artery.

Seen in long-term perspectiye the discovery of X-rays and their use as a diagnostic agent must surely rank as one of the major advances in medicine, Though of less immediate practical benefit than were either anaesthesia or antisepsis, the scientific importance was greater and even now, after more than fifty years, new techniques are still being evolved with resulting increases in knowledge. Among the many sub-divisions of radiology the introduction of contrast radiography in exploring the vascular pattern of organs otherwise inaccessible, has been one of the more recent and most fruitful developments. A striking instance is the use of percutaneous carotid angiography with the consequent recognition of thrombosis of the internal carotid artery. No doubt from time to time an inquisitive morbid anatomist had inspected the carotid arteries in the neck and found one or other occluded, but the fact passed unrecorded and was doubtless regarded as nothing more than